Technical Field
The present disclosure relates to the field of near field communication (NFC) communications, and in particular to an NFC device with multiple secure elements and to a method of routing messages in such a device.
Description of the Related Art
Mobile telephones and other types of mobile devices are increasingly being equipped with near field communication (NFC) interfaces, which enable them to perform electromagnetic transponder functions in addition to their other functions. In particular, such devices are able to emulate the functions of an electromagnetic transponder, which could be of the contactless card type, or the contactless reader type. Such functionality for example enhances the mobile device, by allowing it to be used for various applications, for example as an electronic wallet allowing payments to be made for accessing services such as transport networks.
To emulate the operation of a contactless card, the mobile device is generally equipped with a contactless front-end integrated circuit (CLF), also called an NFC router. This router is equipped with a radio frequency (RF) transceiver front-end coupled to a low-range antenna to match the communication capabilities of an electromagnetic transponder. In some applications, one or more secure elements (SE) or embedded secure elements (eSE), either integrated in the mobile device or contained in a micro-circuit of the USIM (universal subscriber identification module) or μSD (micro secure digital), can be used to provide authentication and other functions.
The NFC router comprises an NFC routing table, which indicates to which hardware the NFC messages received by the NFC router should be routed. For example, some NFC messages, such as those relating to certain types of electronic payment, are to be routed to a secure element of the mobile device. For instance, a VISA application may be running in communication with a Secure Element of a USIM (the name “VISA” may correspond to registered trademarks).
In some cases, the mobile device comprises more than one secure element, and there may be one or more applications stored by each secure element that is capable of handling a given transaction. In such a case, it is desirable that the mobile device is capable of selecting the application to be used among the available applications on all secure elements.
However, a difficulty is that the NFC router is not aware of the list of applications stored by each secure element. Furthermore, when an RF message is received and needs to be routed to a secure element, it is not permitted and nor is there time to interrogate all of the secure elements in order to obtain the lists of applications available on each secure element. There is thus a need in the art for a solution that addresses some or all of these difficulties.